Field
The present disclosure relates to an accessory apparatus attachable to an interchangeable lens attached to an imaging apparatus.
Description of the Related Art
In a camera system including a camera body and an interchangeable lens detachably attached to the camera body, a drive unit is known as an accessory apparatus for driving a magnification-varying lens included in the interchangeable lens. Such an accessory apparatus is detachably attached to the interchangeable lens. Japanese Patent Application Laid-Open No. 2015-94863 discusses a camera system in which an interchangeable lens and a drive unit communicate with each other to transmit and receive position information of members to be driven by the drive unit.
A type of camera system is known that switches between an active mode and a power-saving mode. The power-saving mode consumes less power than the active mode. Japanese Patent Application Laid-Open No. 2014-235449 discusses a camera system including a camera body and an accessory apparatus attached to the camera body. The accessory apparatus sets a power mode according to a command to shift to a power-saving mode received from the camera body.
In general, the power mode of an accessory apparatus such as a drive unit is set according to the power mode of a camera body and an interchangeable lens to which the accessory apparatus is attached. In the camera system discussed in Japanese Patent Application Laid-Open No. 2014-235449, when the camera body enters the power-saving mode, the camera body transmits a command to enter the power-saving mode to the accessory apparatus.
The interchangeable lens attached to the camera body and the accessory apparatus attached to the interchangeable lens can be configured such that, following the shifting of the interchangeable lens to the power-saving mode, the accessory apparatus also enters the power-saving mode. An interchangeable lens generally enters the power-saving mode based on a power-saving command from a camera body, and the camera body can frequently transmit the power-saving command to the interchangeable lens depending on the settings of the camera body. In this case, if the accessory apparatus is shifted to the power-saving mode following the shifting of the interchangeable lens to the power-saving mode as described above, the accessory apparatus will frequently enter the power-saving mode.
When the accessory apparatus is in the power-saving mode, it is difficult to activate the accessory apparatus immediately after a user performs an operation on the accessory apparatus. Therefore, convenience as an imaging system will be lost if the accessory apparatus frequently enters the power-saving mode. In contrast, if the accessory apparatus constantly remains in the active mode and does not enter the power-saving mode, a large amount of power will be consumed by the accessory apparatus.